Continental Race Lite has removable cores.

I run Bontrager TLR, based on its excellent performance in butyl tubes in the "Sealant Test - Part 2" published on another website I probably can't link from here.

In practice, it's actually sealed a handful of punctures (thorns and glass), but unfortunately, one of the thorns sealed with very low pressure left, which I didn't notice all the way down a fast descent with a sharp turn at the bottom. Crashed in the turn. I might have been better off if it had lost all pressure on the climb, allowing me to notice beforehand and change the tube.